Thank you for your question.
I am sorry you are having a problem with the mower. White or light colored smoke means the engine is burning oil. If you just added oil before it started smoking, I suspect it is over filled. First, check the oil and adjust it if needed. Once you have the oil level adjusted, remove the air filter to see if it is soaked with oil. If it is, the filter needs to be replaced. The part can be ordered from the following link.
Craftsman mower parts
Before installing the new filter, wipe up any access oil first. Then start the mower and let it run for 5 minutes. The engine will smoke for a while. This is ok it is just burning off the oil in the muffler. After the engine stops smoking, turn it off and install the air filter. Then you can resume normal operation.
I hope this is helpful. Please let me know if you need further assistance, on the mower.
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